<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_View
 * @subpackage Helper
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @version    $Id: DeclareVars.php 16222 2009-06-21 19:55:20Z thomas $
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */

/** Zend_View_Helper_Abstract.php */
require_once 'Zend/View/Helper/Abstract.php';

/**
 * Helper for declaring default values of template variables
 *
 * @package    Zend_View
 * @subpackage Helper
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_View_Helper_DeclareVars extends Zend_View_Helper_Abstract
{
	/**
	 * The view object that created this helper object.
	 * @var Zend_View
	 */
	public $view;

	/**
	 * Declare template vars to set default values and avoid notices when using strictVars
	 *
	 * Primarily for use when using {@link Zend_View_Abstract::strictVars() Zend_View strictVars()},
	 * this helper can be used to declare template variables that may or may
	 * not already be set in the view object, as well as to set default values.
	 * Arrays passed as arguments to the method will be used to set default
	 * values; otherwise, if the variable does not exist, it is set to an empty
	 * string.
	 *
	 * Usage:
	 * <code>
	 * $this->declareVars(
	 *     'varName1',
	 *     'varName2',
	 *     array('varName3' => 'defaultValue',
	 *           'varName4' => array()
	 *     )
	 * );
	 * </code>
	 *
	 * @param string|array variable number of arguments, all string names of variables to test
	 * @return void
	 */
	public function declareVars()
	{
		$args = func_get_args();
		foreach($args as $key) {
			if (is_array($key)) {
				foreach ($key as $name => $value) {
					$this->_declareVar($name, $value);
				}
			} else if (!isset($view->$key)) {
				$this->_declareVar($key);
			}
		}
	}

	/**
	 * Set a view variable
	 *
	 * Checks to see if a $key is set in the view object; if not, sets it to $value.
	 *
	 * @param  string $key
	 * @param  string $value Defaults to an empty string
	 * @return void
	 */
	protected function _declareVar($key, $value = '')
	{
		if (!isset($this->view->$key)) {
			$this->view->$key = $value;
		}
	}
}
